Core of a spool for receiving self-adhesive tapes



,1963 w. R. RwiLKE 3,107,874

CORE OF A SPOOL FOR RECEIVING SELF-ADHESIVE TAPES Original Filed Dec. 3, 1959 Jnvenlor:

Werner Intel" Fer-d/mwa h I/lre 3,107,874 CORE OF A SPGGL FUR RECEIVING SELF-ADHESIVE TAIES Werner R. F. Wiilre, Hamburg, Germany, assignor to P. Beiersdorf and Company A.G., Hamburg, Germany Continuation of application Ser. No. 857,043, Dec. 3, [959. This application Dec. '7, 1961, Ser. No. 162,625 Claims priority, application Germany Dec. 5, 1958 1 Claim. (Cl. 242-585) Adhesive tapes with pressure-sensitive self-adhesive layers are usually sold in the form of rolls wound upon cylindrical cores of metal, cardboard or plastic material. When winding an adhesive tape on a resilient material, stresses are set up in the windings which are increased by atmospheric influences, especially by the influence of atmospheric moisture on hygroscopic material. As a result of such stresses the adhesive tape wound on the core of a spool tends to be pressed out laterally, and the individual windings tend to slip off the core, which will occur especially when the rolls are stored over long periods of time under unfavourable conditions. The ends of the rolls of adhesive tape then assume an irregular conical shape. This phenomenon is known in expert circles as telescoping. Rolls of adhesive tape defonmed in this way are no longer adapted for insertion into the dispensing devices designed for use in connection with such tapes.

In order to prevent such telescoping it has been proposed to apply protective sheets to the ends of the roll of adhesive tape, said sheets consisting of a material which is substantially impervious to atmospheric moisture. It has further been proposed to make the core usually consisting of cardboard impervious to atmospheric moisture by impregnation or by applying a coating of varnish, or to provide the whole surface of the roll of adhesive tape with a coating of varnish impervious to atmospheric moisture, said varnish coating being bonded to the surface of the roll under application of heat and pressure.

Further, it has been proposed to wind the adhesive tape onto the core as loosely as possible so that no material stresses can be set up upon shrinking.

Further, it has been recommended to provide the core of the spool with a layer of corrugated cardboard designed to absorb the stresses in the adhesive tape.

All these measures are complicated, being costly in labor and material, and have not proved successful in the long run.

It has been found that telescoping of adhesive tapes wound into rolls can be eliminated by using a preferably cylindrical core of an elastic material being provided with apertures extending over part of the width of the core from both edges and preferably parallel to the longitudinal axis of the core. A core of this configuration absorbs the stresses developed in the coiled adhesive tape without telescoping of the adhesive tape.

FIGURE '1 is a perspective view showing a roll of adhesive tape wound on a core;

atent iwld'ii Patented Get. 22, 1963 FIGURE 2 is a perspective view of the core by itself;

FIGURE 3 illustrates the development of the core shown in FIGURE 2 from a fiat piece of material.

The apertures in the core of the spool extend alternately from both edges of the core. At least two apertures must be provided. However, it is preferable to provide a plurality of apertures equally spaced on the periphery of the core of the spool. The length of the apertures can be approximately one-half of the width of the core of the spool. These dimensions may be varied to both sides.

Referring to the drawing, the reference numeral 1 generally designates a roll of adhesive tape wound on a core 3 provided with eight apertures 2.

Such cores of spools of an elastic material, for example of polyethylene, can be easily produced in one operation. The adhesive tape is applied to the core in the conventional manner. They can be used without any difiiculty because the adhesive tape is applied to the core in the same manner as with the known cores of spools and the same devices can be used.

This application is a continuation of my pending application Serial No. 857,043, filed December 3, 1959, now abandoned.

What 'I claimis:

In combination, 'a cylindrical resilient plastic member having a diameter substantially greater than its width, said member having a plurality of elongated slots extending completely through the thickness of said member and extending parallel to the central axis of said member and parallel to each other, said slots extending from the edges of said cylindrical member inwardly toward its center, said slots having a length substantially equal to half the distance of the width of said cylindrical member with adjacent slots extending inwardly from opposite edges of said member, said slots being spaced around the circumference of said cylindrical member equidistant from each other, and a roll of pressure sensitive self-adhesive tape disposed on the outer circumferential surface of said cylindrical member consisting of a plurality of individual coils of tape wound tightly in successive layers one upon the other from a continuous piece of material of elongated rectangular configuration, with the edges of said tape being substantially coextensive with the side edges of said cylindrical member, whereby said combination compensates against telescoping of said coils by the yieldability of the edges of said cylindrical member.

References Cited in the file of this patent UNITED STATES PATENTS 2,350,369 Sa-mpair et al June 6, 1944 2,659,543 Guyer Nov. 17, 1953 2,953,313 Csutor Sept. 20, 1960 FOREIGN PATENTS 1,047,235 France July 22, 1953 532,825 Italy Sept. 9, 1955 

